diff --git a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
index b7e79d0bf4a7..b87fea901489 100644
--- a/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
+++ b/arch/arm/boot/dts/sun7i-a20-cubietruck.dts
@@ -34,6 +34,7 @@ mmc3: mmc@01c12000 {
 			pinctrl-names = "default";
 			pinctrl-0 = <&mmc3_pins_a>;
 			vmmc-supply = <&reg_vmmc3>;
+			bus-width = <4>;
 			non-removable;
 			status = "okay";
 		};